/*

 * Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * @test

 * @bug 4533691 7129185

 * @summary Unit test for Collections.emptyNavigableMap

 * @run testng EmptyNavigableMap

 */

import java.math.BigInteger;

import java.util.Arrays;

import java.util.Collection;

import java.util.Collections;

import java.util.Comparator;

import java.util.Iterator;

import java.util.NavigableMap;

import java.util.SortedMap;

import java.util.TreeMap;

import org.testng.annotations.Test;

import org.testng.annotations.DataProvider;

import static org.testng.Assert.fail;

import static org.testng.Assert.assertTrue;

import static org.testng.Assert.assertFalse;

public class EmptyNavigableMap {

    public static <T> void assertInstance(T actual, Class<? extends T> expected) {

        assertInstance(expected.isInstance(actual), null);

    }

    public static <T> void assertInstance(T actual, Class<? extends T> expected, String message) {

        assertTrue(expected.isInstance(actual), ((null != message) ? message : "")

            + " " + (actual == null ? "<null>" : actual.getClass().getSimpleName()) + " != " + expected.getSimpleName() + ". ");

    }

    public static <T extends Throwable> void assertEmptyNavigableMap(Object obj) {

        assertInstance(obj, NavigableMap.class);

        assertTrue(((NavigableMap)obj).isEmpty() && (((NavigableMap)obj).size() == 0));

    }

    public static <T extends Throwable> void assertEmptyNavigableMap(Object obj, String message) {

        assertInstance(obj, NavigableMap.class, message);

        assertTrue(((NavigableMap)obj).isEmpty() && (((NavigableMap)obj).size() == 0),

            ((null != message) ? message : "") + " Not empty. ");

    }

    public interface Thrower<T extends Throwable> {

        public void run() throws T;

    }

    public static <T extends Throwable> void assertThrows(Thrower<T> thrower, Class<T> throwable) {

        assertThrows(thrower, throwable, null);

    }

    public static <T extends Throwable> void assertThrows(Thrower<T> thrower, Class<T> throwable, String message) {

        Throwable result;

        try {

            thrower.run();

            fail(((null != message) ? message : "") + "Failed to throw " + throwable.getCanonicalName() + ". ");

            return;

        } catch (Throwable caught) {

            result = caught;

        }

        assertInstance(result, throwable, ((null != message) ? message : "") + "Failed to throw " + throwable.getCanonicalName() + ". ");

    }

    public static final boolean isDescending(SortedMap<?,?> set) {

        if (null == set.comparator()) {

            // natural order

            return false;

        }

        if (Collections.reverseOrder() == set.comparator()) {

            // reverse natural order.

            return true;

        }

        if (set.comparator().equals(Collections.reverseOrder(Collections.reverseOrder(set.comparator())))) {

            // it's a Collections.reverseOrder(Comparator).

            return true;

        }

        throw new IllegalStateException("can't determine ordering for " + set);

    }

    /**

     * Tests that the comparator is {@code null}.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testComparatorIsNull(String description, NavigableMap<?,?> navigableMap) {

        Comparator comparator = navigableMap.comparator();

        assertTrue(comparator == null || comparator == Collections.reverseOrder(), description + ": Comparator (" + comparator + ") is not null.");

    }

    /**

     * Tests that contains requires Comparable

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testContainsRequiresComparable(String description, NavigableMap<?,?> navigableMap) {

        assertThrows(() -> {

            navigableMap.containsKey(new Object());

        },

            ClassCastException.class,

            description + ": Compareable should be required");

    }

    /**

     * Tests that the contains method returns {@code false}.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testContains(String description, NavigableMap<?,?> navigableMap) {

        assertFalse(navigableMap.containsKey(new Integer(1)),

            description + ": Should not contain any elements.");

        assertFalse(navigableMap.containsValue(new Integer(1)),

            description + ": Should not contain any elements.");

    }

    /**

     * Tests that the containsAll method returns {@code false}.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testContainsAll(String description, NavigableMap<?,?> navigableMap) {

        TreeMap treeMap = new TreeMap();

        treeMap.put("1", 1);

        treeMap.put("2", 2);

        treeMap.put("3", 3);

        assertFalse(navigableMap.equals(treeMap), "Should not contain any elements.");

    }

    /**

     * Tests that the iterator is empty.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testEmptyIterator(String description, NavigableMap<?,?> navigableMap) {

        assertFalse(navigableMap.keySet().iterator().hasNext(), "The iterator is not empty.");

        assertFalse(navigableMap.values().iterator().hasNext(), "The iterator is not empty.");

        assertFalse(navigableMap.entrySet().iterator().hasNext(), "The iterator is not empty.");

    }

    /**

     * Tests that the set is empty.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testIsEmpty(String description, NavigableMap<?,?> navigableMap) {

        assertTrue(navigableMap.isEmpty(), "The set is not empty.");

    }

    /**

     * Tests the headMap() method.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testHeadMap(String description, NavigableMap navigableMap) {

        assertThrows(

            () -> { NavigableMap ss = navigableMap.headMap(null, false); },

            NullPointerException.class,

            description + ": Must throw NullPointerException for null element");

        assertThrows(

            () -> { NavigableMap ss = navigableMap.headMap(new Object(), true); },

            ClassCastException.class,

            description + ": Must throw ClassCastException for non-Comparable element");

        NavigableMap ss = navigableMap.headMap("1", false);

        assertEmptyNavigableMap(ss, description + ": Returned value is not empty navigable set.");

    }

    /**

     * Tests that the size is 0.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testSizeIsZero(String description, NavigableMap<?,?> navigableMap) {

        assertTrue(0 == navigableMap.size(), "The size of the set is not 0.");

    }

    /**

     * Tests the subMap() method.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testSubMap(String description, NavigableMap navigableMap) {

        assertThrows(

            () -> {

                SortedMap ss = navigableMap.subMap(null, BigInteger.TEN);

            },

            NullPointerException.class,

            description + ": Must throw NullPointerException for null element");

        assertThrows(

            () -> {

                SortedMap ss = navigableMap.subMap(BigInteger.ZERO, null);

            },

            NullPointerException.class,

            description + ": Must throw NullPointerException for null element");

        assertThrows(

            () -> {

                SortedMap ss = navigableMap.subMap(null, null);

            },

            NullPointerException.class,

            description + ": Must throw NullPointerException for null element");

        Object obj1 = new Object();

        Object obj2 = new Object();

        assertThrows(

            () -> {

                SortedMap ss = navigableMap.subMap(obj1, BigInteger.TEN);

            },

            ClassCastException.class, description

            + ": Must throw ClassCastException for parameter which is not Comparable.");

        assertThrows(

            () -> {

                SortedMap ss = navigableMap.subMap(BigInteger.ZERO, obj2);

            },

            ClassCastException.class, description

            + ": Must throw ClassCastException for parameter which is not Comparable.");

        assertThrows(

            () -> {

                SortedMap ss = navigableMap.subMap(obj1, obj2);

            },

            ClassCastException.class, description

            + ": Must throw ClassCastException for parameter which is not Comparable.");

        // minimal range

        navigableMap.subMap(BigInteger.ZERO, false, BigInteger.ZERO, false);

        navigableMap.subMap(BigInteger.ZERO, false, BigInteger.ZERO, true);

        navigableMap.subMap(BigInteger.ZERO, true, BigInteger.ZERO, false);

        navigableMap.subMap(BigInteger.ZERO, true, BigInteger.ZERO, true);

        Object first = isDescending(navigableMap) ? BigInteger.TEN : BigInteger.ZERO;

        Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;

            assertThrows(

                () -> {

                    navigableMap.subMap(last, true, first, false);

                },

                IllegalArgumentException.class, description

                + ": Must throw IllegalArgumentException when fromElement is not less than toElement.");

        navigableMap.subMap(first, true, last, false);

    }

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testSubMapRanges(String description, NavigableMap navigableMap) {

        Object first = isDescending(navigableMap) ? BigInteger.TEN : BigInteger.ZERO;

        Object last = (BigInteger.ZERO == first) ? BigInteger.TEN : BigInteger.ZERO;

        NavigableMap subMap = navigableMap.subMap(first, true, last, true);

        // same subset

        subMap.subMap(first, true, last, true);

        // slightly smaller

        NavigableMap ns = subMap.subMap(first, false, last, false);

        // slight expansion

        assertThrows(() -> {

            ns.subMap(first, true, last, true);

        },

            IllegalArgumentException.class,

            description + ": Expansion should not be allowed");

        // much smaller

        subMap.subMap(first, false, BigInteger.ONE, false);

    }

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testheadMapRanges(String description, NavigableMap navigableMap) {

        NavigableMap subMap = navigableMap.headMap(BigInteger.ONE, true);

        // same subset

        subMap.headMap(BigInteger.ONE, true);

        // slightly smaller

        NavigableMap ns = subMap.headMap(BigInteger.ONE, false);

        // slight expansion

        assertThrows(() -> {

            ns.headMap(BigInteger.ONE, true);

        },

            IllegalArgumentException.class,

            description + ": Expansion should not be allowed");

        // much smaller

        subMap.headMap(isDescending(subMap) ? BigInteger.TEN : BigInteger.ZERO, true);

    }

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testTailMapRanges(String description, NavigableMap navigableMap) {

        NavigableMap subMap = navigableMap.tailMap(BigInteger.ONE, true);

        // same subset

        subMap.tailMap(BigInteger.ONE, true);

        // slightly smaller

        NavigableMap ns = subMap.tailMap(BigInteger.ONE, false);

        // slight expansion

        assertThrows(() -> {

            ns.tailMap(BigInteger.ONE, true);

        },

            IllegalArgumentException.class,

            description + ": Expansion should not be allowed");

        // much smaller

        subMap.tailMap(isDescending(subMap) ? BigInteger.ZERO : BigInteger.TEN, false);

    }

    /**

     * Tests the tailMap() method.

     */

    @Test(dataProvider = "NavigableMap<?,?>", dataProviderClass = EmptyNavigableMap.class)

    public void testTailMap(String description, NavigableMap navigableMap) {

        assertThrows(() -> {

            navigableMap.tailMap(null);

        },

            NullPointerException.class,

            description + ": Must throw NullPointerException for null element");

        assertThrows(() -> {

            navigableMap.tailMap(new Object());

        }, ClassCastException.class);

        NavigableMap ss = navigableMap.tailMap("1", true);

        assertEmptyNavigableMap(ss, description + ": Returned value is not empty navigable set.");

    }

    @DataProvider(name = "NavigableMap<?,?>", parallel = true)

    public static Iterator<Object[]> navigableMapsProvider() {

        return makeNavigableMaps().iterator();

    }

    public static Collection<Object[]> makeNavigableMaps() {

        return Arrays.asList(

            new Object[]{"UnmodifiableNavigableMap(TreeMap)", Collections.unmodifiableNavigableMap(new TreeMap())},

            new Object[]{"UnmodifiableNavigableMap(TreeMap.descendingMap()", Collections.unmodifiableNavigableMap(new TreeMap().descendingMap())},

            new Object[]{"UnmodifiableNavigableMap(TreeMap.descendingMap().descendingMap()", Collections.unmodifiableNavigableMap(new TreeMap().descendingMap().descendingMap())},

            new Object[]{"emptyNavigableMap()", Collections.emptyNavigableMap()},

            new Object[]{"emptyNavigableMap().descendingMap()", Collections.emptyNavigableMap().descendingMap()},

            new Object[]{"emptyNavigableMap().descendingMap().descendingMap()", Collections.emptyNavigableMap().descendingMap().descendingMap()}

        );

    }

}